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Updated: Jul 3, 2026
11:12
Identification of protein complexes with quantitative proteomics in S. cerevisiae
Published on: March 4, 2009
The SNARE complex from yeast is partially unstructured on the membrane
Zengliu Su1, Yuji Ishitsuka, Taekjip Ha
1Department of Biochemistry, Biophysics, and Molecular Biology, Iowa State University, Ames, IA 50011, USA.
Structure (London, England : 1993)
|July 10, 2008
Summary
SNARE proteins mediate vesicle fusion. The SN2 motif is unstructured on membranes, but stabilizes fusion, highlighting the membrane
Area of Science:
- Molecular biology
- Cellular trafficking
- Membrane fusion
Background:
- SNARE proteins mediate vesicle docking and fusion through a four-helix bundle.
- In yeast, Sso1p and Snc2p provide one SNARE motif each, while Sec9 provides two (SN1 and SN2).
Purpose of the Study:
- To investigate the structural dynamics of the SN2 SNARE motif.
- To determine the role of the SN2 motif in membrane fusion.
Main Methods:
- Electron Paramagnetic Resonance (EPR) spectroscopy
- Site-directed mutagenesis (proline substitutions)
Main Results:
- The SN2 motif is partially unstructured on the membrane but fully structured in solution.
- The membrane acts as a destabilizing factor for the SN2 motif.
- Proline mutations in SN2 did not affect docking but significantly reduced lipid mixing rates.
Conclusions:
- The SN2 motif plays a critical role in the transition from vesicle docking to membrane fusion.
- Membrane-induced structural changes in SNARE complexes regulate fusion dynamics.
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